Three major U.S. carriers have agreed not to charge their customers for premium text messages, which have emerged as a route for unauthorized third-party charges on mobile phone bills.

AT&T Mobility, Sprint and T-Mobile will not charge their customers for commercial Premium Short Messaging Services, which gave users the ability to purchase or subscribe to messaging programs provided by third-party content providers, Vermont Attorney General William Sorrell said in a statement on Thursday.

Forty-five states, including Vermont, Delaware, Florida, Maryland, Oregon, Texas and Washington, have been in discussions aimed at stopping mobile “cramming,” which essentially refers to unauthorized third-party charges that appear on mobile phone bills. PSMS account for the majority of third-party charges on cell phones but also for a large majority of cramming complaints, Sorrell said.

Verizon Wireless is winding down its premium messaging business, though it was not part of the announcement by Sorrell. Its General Counsel William B. Petersen said in a statement that the operator had previously decided to exit the premium messaging business because of changes in the ways customers access information as well as recent allegations that third-parties have engaged in improper conduct in providing the premium services to its customers.

You can still donate via text

The change may not affect text-to-donate for charitable programs and text-to-contribute for political campaigns. Sorrell said two carriers had confirmed that they will continue to allow charitable donations to be billed through PSMS. T-Mobile, for example, said it is stopping as soon as possible all billing for premium text services, except for charitable and political giving.

“Despite protections and processes put in place by T-Mobile and the industry, not all premium text message (SMS) vendors have acted responsibly,” T-Mobile wrote on its support page. Standard messaging campaigns like voting on shows like American Idol will continue unaffected, it added.

Verizon also said it would continue to support text-to-donate for charitable programs and text-to-contribute for political campaigns that use the technology.

“We are pleased that AT&T, Sprint and T-Mobile have decided to stop the flow of money from the pockets of ordinary people to the bank accounts of scam artists,” Sorrell said. He urged other carriers to follow their lead.

60 percent of third-party charges placed on the mobile phone bills of the people of Vermont were unauthorized.

Cramming on cell phones and landlines is estimated to cost Americans $2 billion a year. In May, the attorney general released a survey that showed that 60 percent of third-party charges placed on the mobile phone bills of the people of Vermont were unauthorized.

On Thursday, the operators of Wise Media in Atlanta agreed to settle with the U.S. Federal Trade Commission charges that they crammed $10 million worth of charges onto mobile phone users’ bills without their consent.

The FTC charged the company for sending text messages with horoscopes, flirting and love tips and other information at $9.99 per month, without customers’ permission.

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